private void loadnoiseToolStripMenuItem_Click(object sender, EventArgs e)
{
var ofd = new OpenFileDialog
{
InitialDirectory = @"D:\Docs\Research\DATABASE\Various\Фоновые звуки"
};
if (ofd.ShowDialog() != DialogResult.OK)
{
return;
}
using (var stream = new FileStream(ofd.FileName, FileMode.Open))
{
var waveFile = new WaveFile(stream);
_bitDepth = waveFile.WaveFmt.BitsPerSample;
_noise = waveFile[Channels.Average];
}
_noise.Amplify(0.2f);
if (_noise.SamplingRate != _signal.SamplingRate)
{
_noise = Operation.Resample(_noise, _signal.SamplingRate);
}
noisePlot.Signal = _signal + _noise;
}
protected override DiscreteSignal Render(NoteSegment segment)
{
DiscreteSignal mainSignal = null;
if (segment is PercussionNoteSegment percussionNoteSegment)
{
mainSignal = GetPercussionSignal(percussionNoteSegment.PercussionType, percussionNoteSegment.DurationSamples);
}
else if (segment is MelodicNoteSegment melodicNoteSegment)
{
// Combine a Sine wave and a Square wave
mainSignal = SignalHelper.GetSine(melodicNoteSegment.Frequency, melodicNoteSegment.DurationSamples);
mainSignal.CombineAdd(SignalHelper.GetSquare(melodicNoteSegment.Frequency, melodicNoteSegment.DurationSamples));
}
float velocityMultiplier = segment.Velocity / 127f; // Velocity ranges from 0 - 127
// A simple way of doing an equalizer
float balanceMultiplier = BalanceProvider.GetMultiplier(segment);
// Scale the signals based on their velocity and balance multipliers
mainSignal.Amplify(velocityMultiplier * balanceMultiplier);
mainSignal.ApplyAdsr(AdsrEnvelopeProvider.CreateEnvelope(segment));
return(mainSignal);
}
// Make the maximum amplitudes equal to the given maximum amplitude
// Theoretically, float values can range from [-1, 1] though at one point (for some reason) I was under the impressing that 1 would clip to 0
// I think that was according to this: https://stackoverflow.com/questions/12112945/audio-units-samples-value-range
public static void ScaleAmplitude(this DiscreteSignal mainSignal, float maximumAmplitude = 1f)
{
if (maximumAmplitude < -1 || maximumAmplitude > 1)
{
throw new ArgumentOutOfRangeException("Amplitude must be in range [-1f, 1f].");
}
if (mainSignal.Samples.Length == 0)
{
throw new ArgumentException("Signal has no samples.");
}
// Amplify based on the maximum / minimum amplitues so that the new max/min are 1
float currentMax = mainSignal.Samples.Max();
float currentMin = mainSignal.Samples.Min();
float greater = Math.Max(currentMax, Math.Abs(currentMin));
float multiplier = maximumAmplitude / greater;
mainSignal.Amplify(multiplier);
// Check the new minimums and maximums. This might reveal issues with the floating point math
float postAmplifyMax = mainSignal.Samples.Max();
float postAmplifyMin = mainSignal.Samples.Min();
if (postAmplifyMin < -1 || postAmplifyMax > 1)
{
throw new Exception(
string.Format(
"Maximum or minimum amplitude after amplification was not in the valid range of [-1, 1]. Maximum amplitude: {0}; Minimum amplitude: {1}",
postAmplifyMax,
postAmplifyMin
)
);
}
}